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Not a peg or guy rope in sight - inside are shops, cinemas and even a beach

The world's tallest tent has opened to the public in the Central Asian nation of Kazakhstan.

Designed by the British architects Foster & Partners, the Khan Shatyr Entertainment Centre in the capital Astana is 150m (490ft) high.

It opens on the day the city celebrates 13 years as the capital and President Nursultan Nazarbayev his 70th birthday.

The centre has a huge indoor leisure park, designed to be protected from the region's harsh climate.

Khan Shatyr: A 'world within'

The tent is made from three layers of ETFE, a special see-through plastic that allows daylight to wash the interiors while sheltering them from weather extremes

Air is pumped in between the layers inflating them into enormous pillows, giving the tent covering the appearance of a large quilt

The aim is to provide the city with a range of civic, cultural and social amenities sheltered all year round, whatever the weather

In winter, a key challenge is to prevent the formation of ice on the inside of the tent using temperature control and directing warm air currents up the inner fabric surface

The government of Kazakhstan decided to move the capital north to Astana from Almaty in the country's southeast corner because of Almaty's susceptibility to earthquakes and its proximity to the Chinese border